Researchers at the University of Washington will test a once-a-month pill to prevent HIV in women with a new $122 million grant from the Bill and Melinda Gates Foundation.
The grant is one of the first to emerge from the Gates Foundation since Bill and Melinda French Gates announced their divorce in May, and days after Warren Buffett resigned as the organization’s only other trustee. The research is in line with French Gates’ focus on women and girls.
The phase 3 randomized trial will compare the effectiveness of monthly islatravir, a pill in development by Merck, to a standard daily pill that prevents HIV-1.
The daily pill is already approved for HIV prevention, an approach called pre-exposure prophylaxis.
The study will involve 4,500 healthy, HIV-uninfected women in 21 sites in Africa and 500 women in the U.S. Young women in Africa account for approximately 25% of new HIV infections worldwide.
A monthly pill offers the possibility of improved ease of use and adherence. “The whole field is moving toward less adherence-dependent and easier strategies for users of HIV prevention,” Connie Celum, the study’s lead investigator and a UW professor of global health, said in a statement.
Taking a daily pill can also raise barriers in populations where sexual activity is stigmatized. A study last year by Celum Jared Baeten, also a UW global health professor, found that young African women had some of the greatest doubts about pre-exposure prophylaxis, citing issues such as discreet product storage.
“If you only had to take one little tablet once per month and not deal with daily pill-taking and storage, that’s a totally different ball game,” said Celum.
To assess the effectiveness of islatravir, the researchers landed on “double blind, double dummy” trial design. Participants will receive one of two treatments: a daily pre-exposure prophylaxis pill and a monthly placebo that looks like islatravir, or a daily placebo and a monthly dose of islatravir. Researchers will compare the rate of HIV infection of women in the two trial arms.
The new study has begun enrollment in the U.S. and will start screening subjects in Africa this month.
The Gates Foundation has given more than $3 billion HIV grants to date and nearly $3 billion to the Global Fund to Fight AIDS, Tuberculosis, and Malaria.